Influence of oxygen content and surface condition on weld quality of pipeline steels

氧含量和表面状况对管线钢焊缝质量的影响

• 批准号: 491601-2015
• 负责人: Jahazi, Mohammad
• 金额: $ 1.82万
• 依托单位: École de technologie supérieure
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=586988
• 关键词: Influence; oxygen; content; surface; condition

Welded pipeline steels made of 316 or 316L grade stainless steels are widely used in oil and gas industry mainly for the transportation of very corrosive substances. One of the main challenges in welding of these steels is the occurrence of discoloration of the weld region which results often in the rejection of the part. While the industrial practice is based on AWS D18.2 standard; however, the acceptable level of oxygen is not identified and often a weld, which might be good, is rejected because of apparent discoloration. Recent research has indicated that oxygen trapping by the fusion zone is the main source for the discoloration phenomenon. However, the influence of the oxygen level present during welding on the extent of discoloration and level of damage to the microstructure have not been quantified yet. The objective of the present project is to study the influence of oxygen content and surface condition on the extent of discoloration and their impacts on microstructural changes and mechanical properties of 316 and 316L pipeline steels. The generation of these data is a key element in the selection of the appropriate equipment and process conditions for field application by the industrial partner.

由316或316L级不锈钢制成的焊接管线钢广泛用于石油和天然气工业，主要用于输送腐蚀性很强的物质。焊接这些钢的主要挑战之一是焊接区域发生变色，这通常导致零件报废。虽然工业实践是基于AWS D18.2标准;但是，没有确定可接受的氧气水平，并且通常由于明显的变色而拒绝可能良好的焊接。最近的研究表明，氧捕获的融合区是变色现象的主要来源。然而，在焊接过程中存在的氧水平对变色程度和对微观结构的损伤程度的影响尚未被量化。本项目的目标是 研究氧含量和表面状态对316和316L管线钢变色程度的影响及其对组织变化和力学性能的影响。这些数据的生成是工业合作伙伴为现场应用选择适当设备和工艺条件的关键因素。